Questions: A saltwater aquarium can be used to model the ocean. What is one limitation of this model? A. Its temperature can be varied. B. It is shallower than the ocean. C. It can show how certain fish swim in the ocean. D. It can show how light affirgets ocean plants.

The answer is B: It is shallower than the ocean.

Explanation for each option:

A. Its temperature can be varied.

• This is not a limitation of the model. In fact, the ability to vary temperature can be an advantage, allowing researchers to study the effects of different temperatures on marine life.

B. It is shallower than the ocean.

• This is a limitation because a saltwater aquarium cannot replicate the vast depth of the ocean, which affects pressure, light penetration, and the types of organisms that can live at different depths.

C. It can show how certain fish swim in the ocean.

• This is not a limitation. An aquarium can effectively model the swimming behavior of fish, making it a useful tool for studying their movement.

D. It can show how light affects ocean plants.

• This is not a limitation. An aquarium can be used to study the effects of light on marine plants, as it allows for controlled lighting conditions.

In summary, the primary limitation of a saltwater aquarium as a model of the ocean is its inability to replicate the ocean's depth, which is captured in option B.